Air Force Eyes Smaller, Simpler Satellite Designs

Smaller, simpler satellite designs could begin making their way into service for mainstream U.S. Air Force missions in the middle of the next decade, a shift that would break with a longtime tradition of building large, expensive spacecraft for the Pentagon.

This shift from complex and expensive satellites could come about because Gen. William Shelton, Air Force Space Command chief, and other military leaders are embracing the concept of “disaggregation,” or separating capabilities once resident on a single platform onto multiple systems. It could simplify satellite design and create what Shelton calls a “targeting problem” for an adversary looking to cripple U.S. space-based services, by expanding the number of satellites in a constellation.

If disaggregation materializes, it could underpin a shift for major constellations—military satellite communications, missile warning, precision timing and navigation, weather and space situational awareness. While it could prompt an end—or at least slow procurement—of today's satellites, the strategy could also be an opportunity for an industry facing reduced government spending to keep design teams intact.

Two possible near-term opportunities could be Shelton's interest in using a smaller, simpler approach for both the next-generation space situational awareness (SSA) and weather spacecraft.

The Ball Aerospace/Boeing Space-Based Space Surveillance (SBSS) satellite was launched in September 2010 and continues to provide intelligence on objects in geosynchronous (GEO) orbit. But the Air Force is pursing a streamlined design for a follow-on based on SBSS lessons. “We are more mature in our understanding of how SBSS fits into the SSA system,” Doug Loverro, executive director of the USAF Space and Missile Systems Center (SMC), told Aviation Week during the 28th National Space Symposium at Colorado Springs. Since the program was crafted in 2004, new instruments, such as the Space Surveillance Telescope that started operating last year, did not exist. So officials have now narrowed the requirements. “It doesn't take huge optics, nor does it take sophisticated onboard processing to provide . . . data” to customers, says Shelton.

This will squelch Ball/Boeing's hopes of selling an SBSS clone. But it will open the door to other companies and could trigger a ripple effect for the launch industry. With smaller satellite designs, demand for large, expensive launchers such as Delta IV and Atlas V could wane.

In the meantime, Shelton is withholding initial operational capability (IOC) approval for SBSS owing to a faulty piece of electronics. A payload electronics board is resetting itself as the satellite travels through the South Atlantic Anomaly, an intense radiation area. A software fix has already been identified, says USAF Lt. Gen. Ellen Pawlikowski, SMC director, and it will be uploaded this month.

With the demise of the Defense Weather Satellite System, the Pentagon is exploring options for a follow-on to the Defense Meteorological Satellite Program constellation. Two DMSP satellites remain on the ground, so a new one is not needed immediately. Shelton says a simpler design would be attractive.

Additionally, he says the protected, strategic communications mission—providing assured, jam-proof connectivity between the U.S. president and nuclear forces—could be siphoned into a satellite separate from the protected tactical communications requirement. These two are now resident on the Lockheed Martin Advanced Extremely High-Frequency (AEHF) satellite; the second of four is slated for launch as early as May 3. “My instincts tell me . . . we have to disaggregate a little bit,” says Dave Madden, the Air Force's AEHF program manager.

Officials are not abandoning AEHF production altogether but, possibly, eyeing how to augment the current constellation before shifting to a new-architecture approach. The logical place to start would be after the combined buy of AEHFs 5 and 6 (which will be negotiated soon) because there would be a production break if the Air Force opts to buy a seventh vehicle.

One program official advises caution until more studies are complete. The strategic and tactical protected satellite communications missions “were combined for a reason in the first place,” says this official, noting that they share common equipment, such as a digital core processor. “You could end up with 1.5 times the mass on orbit owing to common equipment” being fielded on separate platforms. Additionally, the size of the satellite may decrease by only 25%, an amount that may not change the cost equation.

The advantage, however, could come in allowing for the tactical communication satellites to shed the radiation-hardening requirements so crucial to the strategic satellite designs.

A similar discussion is unfolding in the overhead persistent infrared (OPIR) mission area, which is handled by aging TRW Defense Support Program and new Lockheed Martin Space-Based Infrared System (Sbirs) missile warning satellites. At his previous post as Pentagon procurement chief, Deputy Defense Secretary Ashton Carter commissioned the Joint OPIR Integrated Study Team (Joist) to explore new architecture approaches. The constellation traditionally includes at least four IR satellites in GEO orbit with some additional IR payloads in highly elliptical orbit.

Industry sources say the study, the recommendations of which are classified, outlines a range of options, including a disaggregated architecture. Today, the Sbirs GEO spacecraft carry a scanning sensor—the first of which is slated to be declared operational this summer—as well as a step-staring sensor. These could be hosted on separate platforms, and new technologies could also contribute.

Shelton says the command is “probably solid . . . through Sbirs 6. But beyond that, you can start to think about . . . those kinds of disaggregated concepts.” At that point, the Pentagon could begin to shift to a new architecture.

One other opportunity could arise if the Pentagon opts to break with a longtime tradition and segregate the nuclear-detection system (NDS) payloads from their GPS satellite hosts. “We don't have to go ahead and [integrate] an NDS sensor on a GPS satellite if we don't want to” because the number of sensors required is far fewer than the number of GPS satellites needed, says Loverro. Cutting back on the number of satellites carrying this payload, which is designed to warn of a nuclear blast, could produce “significant” savings, he adds.

Pursuing a GPS design without a nuclear-detection payload could require a new acquisition approach, according to Loverro. This could present an opportunity to Lockheed's longtime GPS rival, Boeing, which was virtually cut out of the business with the Air Force's selection of Lockheed for GPS III.